Use PowerShell to run virus scan on multiple servers - powershell

I'm trying to run a virus scan on a list of servers in our environment. There are hundreds of machines, so we'd like to run the scan (using a command line prompt that we already have) around 10 at a time. We're totally new to PowerShell so any help would be really appreciated. We have a general idea of what commands we need to use -- here's how we think it might work for now:
$server = Get-Content "serverlist.txt"
$server | % {
$VirusScan = { Scan32.exe }
Invoke-Command -ScriptBlock { $VirusScan } -computerName $server -ThrottleLimit 10 -Authentication domain/admin
}
Does anyone have any suggestions on how we might orchestrate this?

I'm using something like this for running tasks in parallel on remote hosts:
$maxSlots = 10
$hosts = "foo", "bar", "baz", ...
$job = {
Invoke-Command -ScriptBlock { Scan32.exe } -Computer $ARGV[0] -ThrottleLimit 10 -Authentication domain/admin
}
$queue = [System.Collections.Queue]::Synchronized((New-Object System.Collections.Queue))
$hosts | ForEach-Object { $queue.Enqueue($_) }
while ( $queue.Count -gt 0 -or #(Get-Job -State Running).Count -gt 0 ) {
$freeSlots = $maxSlots - #(Get-Job -State Running).Count
for ( $i = $freeSlots; $i -gt 0 -and $queue.Count -gt 0; $i-- ) {
Start-Job -ScriptBlock $job -ArgumentList $queue.Dequeue() | Out-Null
}
Get-Job -State Completed | ForEach-Object {
Receive-Job -Id $_.Id
Remove-Job -Id $_.Id
}
Sleep -Milliseconds 100
}
# Remove all remaining jobs.
Get-Job | ForEach-Object {
Receive-Job -Id $_.Id
Remove-Job -Id $_.Id
}

Related

Error on running Pester test using foreach-object -parallel

I have this infrastructure pester test. Code for demonstration purpose:
Describe 'WEB-Tests' {
$servers = 'ServerA','ServerB'
$sessions = #()
foreach ($server in $servers) {
$sessions += New-PSSession -ComputerName $server
}
$sessions | foreach-object {
Context " Service is Running on $($_.ComputerName)" {
$service = invoke-command -session $_ -scriptblock { get-service 'some service' }
It "Service $($service.Name) should be Running" {
$service.Status | Should be "Running"
}
}
}
}
This works fine. If I replace the $sessions|foreach-object with $sessions|foreach-object -Parallel, i get this error -
New-PesterState: C:\Program Files\WindowsPowerShell\Modules\Pester\4.9.0\Functions\Context.ps1:77:128
Line |
77 | … '] .) -TestNameFilter $null -TagFilter #() -SessionState SessionState
| ~~~~~~~~~~~~
| Cannot process argument transformation on parameter 'SessionState'. Cannot convert the "SessionState" value of type "System.String" to type
| "System.Management.Automation.SessionState".
Exception: The Context command may only be used from a Pester test script.
Please suggest on how to achieve parallelism here as there are hundreds of servers.
RESOLVED-I figured out a workaround by using jobs and it serves the purpose.
Describe 'WEB-Tests' {
$servers = 'ServerA','ServerB'
$sessions = #()
foreach ($server in $servers) {
$sessions += New-PSSession -ComputerName $server
}
Get-Job | Remove-Job
invoke-command -session $sessions -scriptblock { get-service W3SVC,WAS } -AsJob
$j = Get-Job | wait-job
($results = $j | Receive-Job) | out-null
Context "IIS Services are Running" {
foreach ($result in $results) {
It "Service $($result.Name) should be Running on $($result.PSComputerName)" {
$result.Status | Should be "Running"
}
}
}
}

PowerShell - How to force timeout Invoke-Command

I would like to force-terminate/timeout a PowerShell Invoke-Command remote session after 20 minutes regardless of whether it's busy or idle.
How do I achieve this? Thanks.
Something like :
$job = Start-Job -ScriptBlock { <# Invoke-Command #> }
$job | Wait-Job -Timeout ( 20 * 60 ) | Remove-Job
PS> invoke_command_responsive -Machine pv3040 -Cmd "get-location"
function invoke_command_responsive {
param(
[string]$Machine,
[string]$Cmd
)
$start_time = Get-Date
$start_dir = better_resolve_path(".")
$watchdog = 8 #seconds
[ScriptBlock]$sb = [ScriptBlock]::Create($opt_cmd)
$j = Start-Job -ScriptBlock {
set-location $using:start_dir | out-null
[ScriptBlock]$sb = [ScriptBlock]::Create($using:cmd)
invoke-command -Computer $using:Machine -ScriptBlock:$sb | out-host
}
# Wait for Job to Complete or TIMEOUT!
while($true) {
if ($j.HasMoreData) {
Receive-Job $j
Start-Sleep -Milliseconds 50
}
$current = Get-Date
$time_span = $current - $start_time
if ($time_span.TotalSeconds -gt $watchdog) {
write-host "TIMEOUT!"
Stop-Job $j
break
}
if (-not $j.HasMoreData -and $j.State -ne 'Running') {
write-host "Finished"
break
}
}
Remove-Job $j
}
function better_resolve_path {
param([string]$path)
$pathfix = $ExecutionContext.SessionState.Path.GetUnresolvedProviderPathFromPSPath($path)
return $pathfix
}

Multi-threading with PowerShell

I have done lots of reading about multi-threading in PowwerShell with Get-Job and Wait-Job but still cant seem to work it out.
Eventually, I will have this as a GUI based script to run and don't want my GUI to freeze up while its doing its task.
The script is looking for Event Logs of my Domain Controllers and then getting the details I want, then outputting them, it works like I need it to.
I can start a job using Invoke-Command {#script goes here} -ComputerName ($_) -AsJob -JobName $_ and the jobs run.
Script below:
Clear-Host
Get-Job | Remove-Job
(Get-ADDomainController -Filter *).Name | ForEach-Object {
Invoke-Command -ScriptBlock {
$StartTime = (Get-Date).AddDays(-4)
Try{
Get-WinEvent -FilterHashtable #{logname='Security'; id=4740;StartTime=$StartTime} -ErrorAction Stop `
| Select-Object * | ForEach-Object {
$Username = $_.Properties[0].Value
$lockedFrom = $_.Properties[1].Value
$DC = $_.Properties[4].Value
$Time = $_.TimeCreated
Write-Host "---------------------------------------------"
Write-Host $Username
Write-Host $lockedFrom
Write-Host $DC
Write-Host $Time
Write-Host "---------------------------------------------"
}#ForEach-Object
}catch [Exception] {
If ($_.Exception -match "No events were found that match the specified selection criteria") {
Write-Host "No events for locked out accounts." -BackgroundColor Red
}#If
}#Try Catch
} -ComputerName ($_) -AsJob -JobName $_ | Out-Null # Invoke-Command
}#ForEach-Object
Currently I have a While loop to tell me its waiting then to show me the result:
(Get-ADDomainController -Filter *).Name | ForEach-Object {
Write-Host "Waiting for: $_."
While ($(Get-Job -Name $_).State -ne 'Completed') {
#no doing anything here
}#While
Receive-Job -Name $_ -Keep
}#ForEach-Object
#clean up the jobs
Get-Job | Remove-Job
Thinking of my GUI (to be created), I will have a column for each Domain Controller and showing results under each heading, how do make it not freeze my GUI and show the results when they arrive?
I know its been asked a few times, but the examples I cant work out.
I would avoid Start-Job for threading - for efficiency try a runspace factory.
This is a basic setup which could be useful (I also have PS 4.0), and open to suggestions/improvements.
$MaxThreads = 2
$ScriptBlock = {
Param ($ComputerName)
Write-Output $ComputerName
#your processing here...
}
$runspacePool = [RunspaceFactory]::CreateRunspacePool(1, $MaxThreads)
$runspacePool.Open()
$jobs = #()
#queue up jobs:
$computers = (Get-ADDomainController -Filter *).Name
$computers | % {
$job = [Powershell]::Create().AddScript($ScriptBlock).AddParameter("ComputerName",$_)
$job.RunspacePool = $runspacePool
$jobs += New-Object PSObject -Property #{
Computer = $_
Pipe = $job
Result = $job.BeginInvoke()
}
}
# wait for jobs to finish:
While ((Get-Job -State Running).Count -gt 0) {
Get-Job | Wait-Job -Any | Out-Null
}
# get output of jobs
$jobs | % {
$_.Pipe.EndInvoke($_.Result)
}

Start services in parallel

I have a script which checks if certain service on different servers is up, if it is not, the script should start the service.
The problem is, it doesn't start the services in parallel, instead it waits until each service is started.
Code:
$server_list = Get-Content -path D:\Path\list_of_servers.txt
$server_list | foreach {
(Get-Service -Name '*Service Name*' -computername $_) | Where-Object {$_.status -eq "Stopped"} | Set-Service -Status Running
}
I know it's due to the way the script is written, but maybe some of you have any suggestions how to make it better?
Cheers!
Here is an example of parallel processing using Powershell and Workflows:
$server_list = Get-Content -path D:\Path\list_of_servers.txt
workflow MyWorkflow
{
foreach -parallel($s in $server_list) {
inlinescript { (Get-Service -Name '*Service Name*' -PSComputerName $s) | Where-Object {$_.status -eq "Stopped"} | Set-Service -Status Running
}
}
}
Using Powershell V2 and jobs
Untested code, but should be close:
$server_list = Get-Content -path D:\Path\list_of_servers.txt
$maxJobs = 5
$scriptblock = {
(Get-Service -Name $args[1] -ComputerName $args[0]) | Where-Object {$_.status -eq "Stopped"} | Set-Service -Status Running
}
foreach ($s in $server_list)
{
$arguments = #($s, $service)
$running = #(Get-Job | Where-Object { $_.State -eq 'Running' })
while ($running.Count -gt ($maxJobs -1)) {
$done = Get-Job | Wait-Job -Any
$running = #(Get-Job | ? {$_.State -eq 'Running'})
}
start-job -scriptblock $scriptblock -ArgumentList $arguments
}
Get-Job | Wait-Job
Get-Job | Receive-Job

Scriptblock works as Invoke-Command, but not as Start-Job

I have written a ScriptBlock that POSTs file uploads to a custom http server and saves the response to disk. It is intended to be used for testing said server and in addition to checking the correct response I'd like to run it in parallel to load the server.
The code in the ScriptBlock was built as separate ps1 script and works. I have then transplanted it into a framework-script using Start-Job for managing the jobs and eventually presenting overall results.
Unfortunately it does not work after that transplantation.
The symptom is that using Start-Job the job never finishes. For testing I have switched to Invoke-Command. A simple Invoke-Command works, InvokeCommand -AsJob does not.
Works:
Invoke-Command -Scriptblock $ScriptBlock -ArgumentList $Name,"C:\Projects\DCA\CCIT\ServiceBroker4\Java\eclipse-workspace\XFAWorker\testdata","P7-T"
Do not work:
Invoke-Command -AsJob -Computer localhost -Scriptblock $ScriptBlock -ArgumentList $Name,"C:\Projects\DCA\CCIT\ServiceBroker4\Java\eclipse-workspace\XFAWorker\testdata","P7-T"
Start-Job -Name $Name -ScriptBlock $Scriptblock -ArgumentList $Name,"C:\Projects\DCA\CCIT\ServiceBroker4\Java\eclipse-workspace\XFAWorker\testdata","P7-T"
The ScriptBlock being used is rather longish. It starts off by declaring Parameters:
$Scriptblock = {
Param (
[string]$JobName,
[string]$path,
[string]$BASEJOBNAME
)
And further down uses HttpWebRequest and a few other .NET classes:
$url = "http://localhost:8081/fillandflatten"
[System.Net.HttpWebRequest] $req = [System.Net.WebRequest]::create($url)
...
$xfabuffer = [System.IO.File]::ReadAllBytes("$path\$BASEJOBNAME.xml")
...
$header = "--$boundary`r`nContent-Disposition: form-data; name=`"xfa`"; filename=`"xfa`"`r`nContent-Type: text/xml`r`n`r`n"
$buffer = [Text.Encoding]::ascii.getbytes($header)
...
[System.Net.httpWebResponse] $res = $req.getResponse()
As described when using Start-Job or Invoke-Command -AsJob the child job started simply remains in Running state forever.
What can cause this behaviour? What can be used to debug it? If there is some error can I force the child-job to terminate and tell me what it does not like?
I am using PowerShell 2.0 on Windows XP.
In the framework I came up with I do the Start-Job (currently just one of them, but I plan to ramp up that number for stress-testing). Then I have a loop waiting for them all to terminate:
do {
$Jobs = #(Get-Job | Where { $_.State -eq "Running" -and $_.Name.StartsWith($BASEJOBNAME) });
$n = $Jobs.Count
if ($n -gt 0)
{
Log -message "Waiting for $n jobs to finish..."
Get-Job | Where { $_.Name.StartsWith($BASEJOBNAME) } | Format-Table -AutoSize -Property Id,Name,State,HasMoreData,Location
start-Sleep -Seconds 3
}
} until ($n -eq 0)
This produces output of the form:
2014-08-01 18:58:52 - Waiting for 1 jobs to finish...
Id Name State HasMoreData Location
-- ---- ----- ----------- --------
2 XFA001 Running True localhost
Forever.
A full minimal test-case is:
# Code for the Jobs:
$Scriptblock = {
[System.Net.HttpWebRequest] $req = [System.Net.WebRequest]::create("http://locahost/index.html")
return "done"
}
# Start a job. Three variants, The Job-based ones hang.
# Invoke-Command -Scriptblock $ScriptBlock
#Invoke-Command -AsJob -Computer localhost -Scriptblock $ScriptBlock
$Job = Start-Job -Name $Name -ScriptBlock $Scriptblock
## The rest of the code is only applicable for the Start-Job-Variant
# Wait for all Jobs to finish
do {
$Jobs = #(Get-Job | Where { $_.State -eq "Running" });
$n = $Jobs.Count
if ($n -gt 0)
{
Write-Host "Waiting for $n jobs to finish..."
Get-Job | Format-Table -AutoSize -Property Id,Name,State,HasMoreData
Start-Sleep -Seconds 3
}
} until ($n -eq 0)
# Get output from all jobs
$Data = ForEach ($Job in (#(Get-Job | Where { $_.Name.StartsWith($BASEJOBNAME) } ))) {
Receive-Job $Job
}
# Clean out all jobs
ForEach ($Job in (#(Get-Job | Where { $_.Name.StartsWith($BASEJOBNAME) } ))) {
Remove-Job $Job
}
# Dump output
Write-Host "Output data:"
$Data | Format-Table
Write-Host ""
This hangs for me. If I comment out the line creating the WebRequest object it works.
Thank you.
When you run Get-Job , does the job's "HasMoreData" properties is "True" ?
If yes, check the output of the job :
Receive-Job <JobName or JobID> -Keep